use separate workers for tile parsing to avoid blocking the threadpool for other libuv actions

1 files changed, 24 insertions, 11 deletions

diff --git a/include/mbgl/util/uv_detail.hpp b/include/mbgl/util/uv_detail.hpp
index 272ca41495..b0b4fe583f 100644
--- a/include/mbgl/util/uv_detail.hpp
+++ b/include/mbgl/util/uv_detail.hpp
@@ -2,6 +2,7 @@
 #define MBGL_UTIL_UV_DETAIL
 
 #include <mbgl/util/ptr.hpp>
+#include <mbgl/util/uv-worker.h>
 
 #include <uv.h>
 
@@ -108,6 +109,22 @@ private:
     uv_once_t o = UV_ONCE_INIT;
 };
 
+class worker {
+public:
+    inline worker(uv_loop_t *loop, unsigned int count, const char *name = nullptr) {
+        uv_worker_init(&w, loop, count, name);
+    }
+    inline ~worker() {
+        uv_worker_close(&w);
+    }
+    inline void add(void *data, uv_worker_cb work_cb, uv_worker_after_cb after_work_cb) {
+        uv_worker_send(&w, data, work_cb, after_work_cb);
+    }
+
+private:
+    uv_worker_t w;
+};
+
 template <typename T>
 class work {
 public:
@@ -115,30 +132,26 @@ public:
     typedef void (*after_work_callback)(T &object);
 
     template<typename... Args>
-    work(const mbgl::util::ptr<loop> &loop, work_callback work_cb, after_work_callback after_work_cb, Args&&... args)
-        : loop(loop),
-          data(std::forward<Args>(args)...),
+    work(worker &worker, work_callback work_cb, after_work_callback after_work_cb, Args&&... args)
+        : data(std::forward<Args>(args)...),
           work_cb(work_cb),
           after_work_cb(after_work_cb) {
-        req.data = this;
-        uv_queue_work(**loop, &req, do_work, after_work);
+        worker.add(this, do_work, after_work);
     }
 
 private:
-    static void do_work(uv_work_t *req) {
-        work<T> *w = static_cast<work<T> *>(req->data);
+    static void do_work(void *data) {
+        work<T> *w = reinterpret_cast<work<T> *>(data);
         w->work_cb(w->data);
     }
 
-    static void after_work(uv_work_t *req, int) {
-        work<T> *w = static_cast<work<T> *>(req->data);
+    static void after_work(void *data) {
+        work<T> *w = reinterpret_cast<work<T> *>(data);
         w->after_work_cb(w->data);
         delete w;
     }
 
 private:
-    mbgl::util::ptr<uv::loop> loop;
-    uv_work_t req;
     T data;
     work_callback work_cb;
     after_work_callback after_work_cb;